Combined radio and phonograph cabinet



May 6, 1930. GOLDSMITH ET AL 1,757,304

COMBINED RADIO AND PHONOGRAPH CABINET Filed April 14, 1925 2 Sheets-Sheet l hwemow I a ALFRED N. GOLDSMITH LAZARUS smwuw l n fmfivflbtowwl M 1930. A. N. GOLDSMITH ET 1,757,304

COMBINED RADIO AND PHONOGRAPH CABINET Filed April 14-, 1925 2 Sheets-Sheet 2 EH E I VIA/G APPA 11 72 5 J/mreM/hns ALFRED N. GOLDSMITH 3 LAZARUS SHAPIRU 35 MM 61 llozwm g Patented May 6, 1930 uni'rso STATES PATENT OFFICE ALFRED N. GOLDSMITH AND LAZARUS SHAPIBO, OF NEW YORK, N. Y., ASSIGNORS TO RADIO CORPORATION OF AMERICA, A CORPORATION OF DELAWARE COMBINED RADIO AND ?HONOGRAPH CABINET Application filed April 14, 1925.

Our invention relates generally to combined radio and phonograph cabinets and has generally for its object to eliminate certain troubles heretofore present in apparatus of this kind and to make better use of elements already used in combined radio and phonograph cabinets.

One of these objects is to provide a method and means for eliminating the troublesome clicking noises delivered by the radio loudspeaker when two metal parts which happen to be separated come into contact. This is accomplished by permanently electrically connecting the metal parts which are liable to come into contact.

Another of these objects is to provide a method and means for using the power supply wires which supply power to the driving motor of the phonograph as an aerial.

Another object is to electrically connect all the various metal masses, which are normally present in apparatus of this kind, together form aerial.

Another object is to provide a double horn having two separate and distinct sound passages, one sound passage being in exclusive communication with the loud-speaker unit of the radio and the other sound passage being in exclusive communication with the phonograph reproducer.

Other objects will be apparent from the following specification and claims when considered with the accompanying drawing in which:

Fig. 1 is a perspective of our combined radio and phonograph cabinet.

Figs. 2 and 3 are details thereof showing the manner of permanently electrically con necting togethertwo of the metal masses, the accidental contact of which, when the radio side is operating, gives the most trouble.

Fig. 4 is a crosssection of the radio side i of the combined cabinet.

Fig. 5 is a schematic diagram illustrating the wire connections between the loop aerial, the various metal elements and motor supply wires of the combined radio and phonograph cabinet.

Referring now to the drawing, our combined cabinet is denoted generally by A. It

Serial No. 22,954.

has two sides denoted generally by B and C, B bein the radio side and C the phonograph side. ltach side has its separate cover 1 and 2.

The phonograph side will first be described. The phonograph side C consists of a chamber 3 enclosed by back wall 4, side wall 5, and separating wall 6. lVithin the lower part of the chamber 3 is mounted the double born 7 having sound passages 8 and 9 separated by partition 7. Mounted over the horn 7 is a wooden mounting plate 11 which is suitably supported between wall 6 and wall 3. Mount ing plate 11 is supported on wall 3 by means of angle iron 17. It will readily be understood that the mounting plate 11 may be in more than one piece. Secured to the mounting plate 11 by means of a metal supporting collar 12 is the metal tone arm 12 which is adapted to swing in a horizontal plane in the usual way. The supporting collar 12 connects with the sound passage 9 so that sound may be conveyed from tone arm 12 out through sound passage 9.

Secured to the under side of mounting plate 11 by means of metal base plate 18 is electric motor 10 for driving the phonograph turn table (not shown). Projecting through a hole in the mounting plate 11 is the turn table shaft 13 adapted to carry the turn table. The shaft 13 is operatively connected to motor 10 as will easily be understood.

The tone arm 12 has a depending metal lever 14 which cooperates with a metal lever 14* of automatic stop mechanism 15 made up of a system of metal levers and which is mounted on the upper side of mounting plate 11. This automatic stop mechanism 15 may be of any common and well-known construction and is for the purpose of stopping the driving motor by opening motor switch 16 when the phonograph recorder has completely traversed the phonograph record. The turn table is omitted for the purpose of showing the automatic stop mechanism. Similarly the reproducer which is mounted at the end of the tone arm 12 is omitted to simplify the drawing. The lever 14? of the stop mechanism 15 and the entire stop mechanism is an electrical contact relation with the base plate 11 and the frame of the motor 10 in the usual construction. Heretofore the tone arm 12 and associated supporting collar 12 was insulated from the motor and associated stop mechanism 15 by the insulating supporting plate :11.

According to the invention a metal strip 19 is led from motor plate 18' to angle iron 17 making good electrical connection with both the motor plate and angle iron for a purpose later described. A metal strip 19 also runs from tone arm supporting collar 12 to angle iron 17 for a similar purpose. These features are shown in detail in Figs. 2 and 3. i

Now referring to the radio side of our combined cabinet, the separating wall 6, back wall 20 and side wall 21 define a space in which the radio apparatus is placed. The lower portion of this space is divided into i-battery compartment 23 and B-battery compartment 24 directly above, and a shelf compartment 25 in front of compartment-s 23 and 24 extending to their joint height. The shelf compartment 25 has shelves 26 therein on which may be placed phonograph record albuins or any other desirable objects.

Mounted in the upper portion of the radio space is the radio catacomb 27 which is supported by a panel 28 liinged to the backwall 20. The catacomb 27 contains variousradio devices and serves as a mounting'for radio tubes 27*. On the panel 28 is mounted the various radio controlling dials and rheosta-ts 29 and 30.

In the side wall 21 is arranged a chamber w ich accommodates ahollow panel 31. The hollow panel is adapted to swing by'means of hinges 32 to positions in various vertical planes. ithin the hollow panel 31 is a loop aerial 33. The adjustability of the loop aerial 83 permits positioning in the direction of maximum energy reception from a given station as will readily be understood.

It has been found heretofore, when operat .4 ing the radio side, that troublesome noises are encountered due to clicking sounds coming forth from the passage 8 of the horn 7 whenever twometal portions normally apart come together. This was true especially if during the radio selection, the depending lever 14 of the tone arm 21 happened to swing over into contact with the lever 14 of automatic stop mechanism- 15.

It has been found that if the tone arm 12 and motor base 18 were placed in permanent conducting relation, no noise would result if the depending; lever 14 on tone arm 12 happened to swing over into contact with lever 14" .of automatic stop mechanism 15.

Our theory of the clicking phenomenon and its cure is that the various metal parts used in a combined machine ofthis kind operate to give a certain distortion of: the electriealfield due to the sending station. So long as their field distribution" is unchanged,

there is no effect on the receiving antenna 33. However, if two metal portions that are separated are suddenly brought together, it means that the two initially separate electrical masses have become one, and the resultant field distribution is changed causing click.

Although for purposes of illustration we have shown only the mass comprising the tone arm 12 and supporting collar l2 permanently connected to the mass comprising the stop mechanism 15 and motor 10, we wish it distinctly understood that any two metal parts which are sometimes in contact and sometimes not in contact may be connected in this manner.

The next feature of the invention calls for putting these connected metal masses to some use. Therefore all of the masses, after they are connected together, are lead by conductors 40 and 61 to the high potential side of the loop 33. The high potential side of the loop is the side connected to the grid of the first tube and the low potential side of the loop is the side connected to the filament of the first tube.

It may be here stated that is has been found in practice that any loop antenna always works better ifsome sort of an additional antenna or some sort of ground is connected thereto. Therefore our invention comprehends not only using these connected metal massesas additional antenna, but makes use of the feed wires which feed the electric motor 10. These feed wires include both the local wiring from thepl-ug 43 and the entire power net-work of the power system supplyingthe power.

Referring particularly to Fig. 5, the plug 43 is for insertion in a suitable socket for supplying power to drive the turn table motor 10. A circuit extending from the plug 43 through motor 10 and switch 16 is composed of wires 50, 51 and 52.

Across the terminals of plug 43 by means of wires 52 and 72 are serially connected condensers 44- and- 45. It should be noted that these condensers 44 and are directly across the terminals of plug 43 and have conductive relation to the power network to which the plug 43 is connected independently of the motor 10 or switch 16. The condensers 44 and 45 will be of sulficiently high impedance to the power current that no appreciable power will be taken thereby. From the common terminals of condensers 44 and 45a wire is led to wires 40 and 61.

Thus it is seen that both the connected metal masses and the-motor supply wires can he made to assist the loop antenna 33 in the reception of energy. However, although we have shown both the connected metal masses and the motor supply wires connected to the high side of the loop for purposes of" illustrationonly, we may connect boththe connected metal masses and the motorsupply wires to the low side of the loop. F urthermore we may connect either the connected metal masses or the motor supply wires to either the high or low side of the loop. We have found that under some conditions, reception is improved by connecting the motor supply wires to the low side of the loop and the connected metal masses to the high side of the loop.

The two passages 8 and 9 of the double horn 7 extend each exclusively to its sound initiating element, the passage 8 extending to the loud-speaker of the radio side (not shown) and the passage 9 extending to the phonograph reproducer as heretofore ex plained. From this it will be seen that each sound passage can be separately designed to give the best qualities, and neither one is affected by conditions in the other as would be the case if we depended on one horn with an acoustic switching means for switching in either the loud-speaker unit or the phonograph unit. It will be understood that the radio receiving apparatus will be suitably connected to the loud speaker unit.

Having described our invention, we feel that we are entitled to all modifications and ramifications thereof as fall fairly within the spirit and scope of the following claims:

1. In a radio cabinet having separate metallic masses which are freely mounted to contact and separate from one another the method of obviating electrical field distor tion caused by such contact and separation which comprises placing said masses in permanent electrically conductive relation.

2. A radio device comprising two relatively movable metallic masses which are mounted to contact with and separate from each other thereby variably distorting an incoming signal wave, receiving apparatus, means connecting one of said masses to said receiving apparatus and means for eliminating the variable distortion of the incoming wave caused by the contact or separation of said movable masses.

3. In a radio receiving apparatus the combination of a cabinet, 2. radio receiving circuit in said cabinet, metallic masses in said cabinet separate from said receiving circuit, means for electrically connecting said masses together, and a lead connecting one of said masses to a desired point on said receiving circuit.

4. In a radio cabinet the combination of a radio receiving circuit, an antenna circuit for said receiving circuit, a plurality of metallic masses in said cabinet and electrical conductors connecting said metallic masses to said antenna circuit.

5. In a combined radio phonograph cabinet the combination of a radio receiving circuit, an antenna circuit for said receiving circuit, a plurality of metallic masses form- 

